Can an employer and/or its representative evaluate your performance base on the tasks that is not explicitly part of your jod description?

i was hired in a manufacturing company as a manufacturing technician. Implicitly, it is defined in my job description that im supposed to be working on a task that is consider as "value added" (directly involved in processing our main product). due to economic difficulties they reassign me to tasks that is indirectly involved in making the products, the job specifically is to prepare and manual transport a certain machine tool that is used in the production. technically this fall under engineering department. note also that this tasks were once assign to contractual employees who they don't provide any such form of performance evaluation.

However, they still evaluate me based on the tasks that i should be doing as a manufacturing personnel. meaning, in the said criteria they still include the following:
1. able to meet the commit number of product outs.
2. must be involved on per process team activity (i don't have this opportunity right now as it is unavailable in our tasks)

therefore i failed miserably on those criterias because in my current tasks it is impossible for me to meet it. Is that fair?

Just one question, is it clearly added in your JD the statement "Any other tasks that maybe assigned from time to time" or anything with the same meaning? the company has the right to evaluate your performance kahit ano pa ito as long you are the person doing the job. -just my opinion.

Just one question, is it clearly added in your JD the statement "Any other tasks that maybe assigned from time to time" or anything with the same meaning? the company has the right to evaluate your performance kahit ano pa ito as long you are the person doing the job. -just my opinion.

What does your Job Description tells you to do ?

well implicitly dapat involve ako sa value added na trabaho.

meaning i expect nag ooperate ako ng process na involve directly sa pag manufacture ng product. since wala na ako access sa tasks imposible ma meet ko yung criteria sa evaluation.

technically nilagay nila ako sa trabaho na involve sa equipment upkeep and maintenance gawain ng engineering department. explicitly sa contract ako po ay manufacturing personnel.

as far as im aware wala po ako natatandaan na part ng jd ko yung vague statement na " any other job from time to time".
other than sensible implicit tasks such as housekeeping, problem diagnostic and relevant material handling which for all intent and purposes limited sa operation na naka assign sa akin. (meaning di po ako required maglinins ng toilet, mag solve ng facility power failure, or mag drive ng cargo truck)